Evolution of Patterned Structures During Growth of GaAs above and Below The Roughening Transition

We report on a study the evolution of the morphology of both patterned and unpatterned GaAs(001) during MBE homoepitaxial growth across the roughening transition temperature [1]. Our previous results [2] for patterned surfaces revealed an initial amplification of the corrugation amplitude at short times and on large lateral length scales, with a transition to decay beyond a critical lateral size which increases monotonically with the thickness grown. Our early results indicate that there is a change in the growth mode above a roughening temperature which leads to a qualitatively different evolution of structures. We investigate in detail the length scale dependence of this difference. *Work supported by the Laboratory for Physical Sciences and an NSF-MRSEC. [1] V. P. Laballa et al. Phys. Rev. Lett. 84, 4152, (2003). [2] S. Shah, et al. Appl. Phys. Lett, 83, 4330, (2003).